old motorhead

I've used 0w40 Mob 1 for years too. I kinda like having 25% more Zn and 22% more Phos vs the recommended Mob 1. Sometimes I run my cars hard in some really hot weather. I wouldn't use it in a stock or low mile Vette. My Vettes usually get a HP injection soon after we meet though.

Not saying anyone should change a program that they're comfortable with. Just my thoughts on it.

http://www.billswebspace.com/mobil_1_product_guide.pdf

AORoads

There could be a big difference!---the C7 engines are completely different from any C6 engine which could lead to a completely different set of tolerances to accommodate higher horsepower, torque, etc. Time marches on---no one would say a '60s, '70s or even '90s car has the same tolerances as a car made last year or 5 years ago, are they?

As to the "backward compatible" for the new, recommended oil for all C7s (2014-2019) of 0W-40, it is a different oil than the currently available domestic or Euro version. Whether it's better or not, Chevrolet and GM are recommending it for all C7s.

One person in C7 said it was ALSO backward compatible to ALL Dexos-recommended Corvettes. Dexos started with the 2011 C6s. So, I asked the question: where does it say that from either GM or Mobil1? So far, it doesn't. I was directed to the Tadge post, it doesn't say it either.

As far as I've seen, GM has not said the new 0W-40 is for C6s of any year, '11 before or after. It may work well, but the question always is: for how long? I trust Mobil1 but they don't offer any warranties. GM does, or used to if the one on your car has expired on your C6. GM also wrote the book on what to use in it. Until that changes, it's your independent call as to what to use.

And to the post that "LDB" made, what he's saying makes sense, but for him and others, the details on the newest Mobil1 oil are not in published print. So, all we are reading is a marketing piece from the oil company. I'm not saying it's untrue or shades the truth but there are some missing pieces of information---for LDB and for me, as well as others on this thread.

FortMorganAl

I've read on the Internet that it is best to use a straight 30W in a '53 Buick so that's what I'm sticking with.

LDB

Agree that data are still missing. The big issue for me is VI improver stability. When I retired in 2010, despite the fact that a few like BMW recommended 0W40, the required VI improvers were not sufficiently stable for 10,000 mile intervals based on the data I saw at the time. It’s certainly possible that they’ve gotten better to the point that they now are. One of the still-missing data points that will be most instructive to me is whether GM continues to recommend 15W50 for track use in the supercharged engines. Logic for placing importance there is that if VI improver fails, 15W50 will only degrade to 15W40 (a 25 spread), while 0W40 would degrade to 0W25. The latter would be a serious problem in a highly loaded engine. So it says to me that if they stick with 15W50 for the track for supercharged engines, they still don’t have full confidence in the VI improver. As to clearances, I can’t rule that out as a factor in their recommendations, but the weight versus oil temperature versus VI improver issue seems more likely to me to be at the heart of things.

ls1121

In my vehicles I use the Mobil 1 Extended Performance oils. My Z28 has 344,000 miles on the Original motor using 10w-30, I change it every 9,000 miles or so and I use the 5w-30 in my 08 LS3.

On another note I replaced the top end on my Z28 at 265,000 and the only visible signs of wear was on 2 of the pushrods on the end connecting the rocker arm, the Chrom-moly shine was gone. That most likely was caused by a piece of dirt getting lodged in there somehow, at least that is what someone has told me as to why it was only on one end of 2 different pushrods. Good info. and thanx to old motorhead for the Chart.

orca1946

In my 1978 Trans am 6.6 I started using Mobil one 5 - 30 and noticed that oil pressure went up to 60. Is that a ok thing over the recommended 10- 30 I used to use?

Bruze

". . . went up to 60." From what?

Were both oils checked under the same conditions? i.e.: A cold idle? Warm idle? Cold highway speed? Warm highway speed?

Either way, that oil isn't going to make any noticeable pressure difference over the previous. If anything, it might be slightly lower when cold, not higher.

CHEV AGAIN

I can't believe that this oil thread has gone 3 pages and the AMSOIL guys haven't shown up!

Mark

Scuba Ghost

Nope.

Vet Interested

They will.....

Jstan2014

Negative. Not changing.

owc6

That's not what my OM says. It says:

"Oil pressure should be 20 to 80 psi (140 to 550 kPa). In certain situations such as long, extended idles on hot days, it could read as low as 6 psi (40 kPa) and still be considered normal"

dmk0210

What are the conditions where you would expect the VI improvers additives to fail?

High heat or long service interval?

I only put about 4k to 5k miles on my oil changes and change it once a year and don't let my oil temp gauge get above 250-260 deg. Is there a realistic risk that the VI improvers additives would fail during those short OICs?

Batman75

I said the same thing in reply 25 but added the low pressure warning light doesn't come on until 3 psi.

Corvette_Ed

5W30 has worked in my 08 since it was born 10 years ago. I don't see any need to change what's already proven to work just fine.

LDB

Not likely to be an issue under those conditions. It’s not an issue of calendar time, it’s an issue of miles and severity. So even if you go to zero on the OLM, if that zero was driven by the one year calendar time with miles still low and not much severe driving, VI improvers should be fine. If you haven’t seen it in other posts, VI improver molecules look like an octopus. When cold, the tentacles curl up tightly around the body so they flow like normal molecules. But when hot, the tentacles fan out and extend from the body, making them resist flow, thus countering the tendency of the base oil to thin out when hot. The problem is that the tentacles can break off, and when they do, they no longer can thicken up the hot oil. But what causes them to break off is wear and tear in a running engine while their tentacles are extended, not sitting around cold with tentacles wrapped around their body in a parked engine.

windyC6

OMG !!!!! Please help us Mr. Wizard !!!!!....

Batman75

You sure are obnoxious. Don't know how old you are but you sometime sound like you are still in junior high. You also have bad taste when it comes to chrome wheels versus black.

dmk0210

Yeah! Burn him, he's a witch! He turned me into a newt!

LDB

You don’t seem very interested in how things work. That’s fine with me. I’m not trying to jam anything down anyone’s throat, I was simply trying to answer a question. Is your suggestion that I should not answer questions, or that I should give better answers? If the latter, what would you suggest I should have said in answer to post #53?